1. Field of the Invention
The present invention relates to an apparatus for treating a semiconductor substrate, and more particularly, to an apparatus for treating a substrate by supplying a plurality of treatment solutions to the substrate.
2. Description of the Related Art
Various processes such as deposition, photolithography, etching, and polishing are performed for manufacturing a semiconductor device. In an etch process, an etching solution or gas is applied to a wafer to remove a layer, an organic material, or particles from the wafer in a predetermined pattern.
Various etching solutions are used for etching a wafer depending on the type of a layer or material to remove from the wafer. In a conventional etching device, a drain tube is connected to a sidewall or bottom wall of a single vessel where a chuck is installed for receiving a wafer. A supply tube is placed above the vessel to supply etching solutions and deionized water to the wafer placed on the chuck. However, when a plurality of etching solutions are sequentially supplied to the wafer for etching the wafer, a discharging etching solution is mixed with a remaining etching solution on the vessel or in the drain tube. Therefore, the discharged etching solution cannot be reused, thereby wasting expensive etching solutions.
Further, when the etching process is performed using different etching devices depending on the types of etching solutions to prevent above-described problems, it takes much more time to carry the wafer from one device to another device, and semiconductor process equipment become larger due to the plurality of etching devices.
Furthermore, pollutant gases such as fumes are generated from etching solutions during an etch process. When the fumes are discharged through the same passage and exhaust tube, the fumes can react with each other in the passage or exhaust tube. In this case, an undesired layer can be deposited on the inner surface of the passage or the exhaust tube, and thus exhaust pressure can be out of a predetermined range, increasing the possibility of process errors. Particularly, when an acid fume and a basic fume are included in the generated pollutant gases, the above-described problems become much more serious due to intensive reaction between the acid fume and the basic fume.